This invention relates to the processing of lengths of flattened flexible polymeric tubes. More particularly this invention relates to means for separating and supporting such lengths either in a stacked or rolled condition for storage or packing and shipment. This invention has specific relation to a method including the use of a separator or spacer for disposition either between or within lengths of uncured or unvulcanized rubbery polymeric tubes for the purpose of preventing the development of edge creases along the edges of the tube lengths.
Those skilled in the art are aware that in the handling of flexible polymeric tubes and particularly uncured or unvulcanized rubber tubes a problem has existed when such tubes are stacked or wound around a cylindrical core or shell while in a flattened condition. This problem relates to the development or formation of edge creases in the enlarged folded edge portions of the tube lengths extending along the longitudinal edges thereof. These edge creases result in a longitudinal thinned out portion which often detrimentally affects the usefulness of the tube. For example, when such tubes are used in lining pipe a thinned out portion may be created in the creased area during inflation of the tube in the pipe or jacket. This same condition can exist when the tube is positioned over a mandre for example, during a hose manufacturing process.
It is assumed that the edge creases are caused by the extra pressure which is created when the tube lengths are stacked or wound upon each other. Previously it has been the practice either to allow each successive tube length to lie directly on the length immediately therebelow or to separate these lengths only by a relatively thin film for example, of polyethylene or holland cloth to essentially prevent adherence of the unvulcaized rubbery polymeric material.
It has been found that the foregoing disadvantages can be overcome by the present invention which will be hereinafter described.